In my opinion, you should keep it all in this thread. If you want to have some inspiration on how to structure the 1st post, look to games like Dating my Daughter, Pine Falls, Double Homework or as mentioned before Daughter for Dessert. You risk that people get confused about where to find the game, and misses that there is a part one or two. You also lose the votes and rating of this thread, whereas, if you keep everything in this thread, at some point, it will probably rise to one of the top spots on the site. You just need to keep the versioning of the game as "Book 2: v0.0.2" or something like it in the future.
As far as the support comment a few posts earlier, I do have a quick suggestion: I personally think the file name should have the name "book 1" in it and not just the current version number. Or else I agree that some people would quickly be confused.